Wireless networks provide network connectivity to mobile communication devices, such as smart phones. The network connectivity may be provided through radio interfaces. Typically, the mobile devices connect to the wireless network through an access point that is part of the network infrastructure. For example, a device may connect to a cellular base station or a wireless local area network (WLAN) access point (e.g., a WiFi access point).
Some techniques may allow devices to establish direct communication paths with one another (e.g., without going through a cellular base station or WiFi access point). For example, devices that are located in proximity to one another may discover one another and subsequently establish direct communication paths with one another. In specifications published by the 3rd Generation Partnership Project (3GPP), direct communication between wireless devices may be referred to as “proximity services” (ProSe). ProSe communications can have a number of advantages, such as improved spectrum utilization, improved overall throughput and performance, and improved energy consumption. In the context of public safety services, ProSe communications can provide an important fallback public safety network that may function when a cellular network (e.g., a 3GPP cellular network) has failed or is unavailable.
A network, such as a 3GPP-based network, may include Lawful Interception (LI) functionality. Under LI, the network provider may enable Law Enforcement Agencies (LEAs) to intercept content and other related information corresponding to traffic of particular mobile devices. For lawful intercept, the target mobile device(s) may need to be identified.
In ProSe communications, a relay device, such as a mobile device acting as a relay device, may be used to couple another mobile device (such as one that is out of the coverage area of the cellular network) to the cellular network. Implementing lawful intercept in this situation can be problematic, however, as the mobile device that is to be targeted for lawful intercept may not be visible to the cellular network.